The invention discloses a wide-range high-resolution surface three-dimensional measurement system with tunable beat-wave linear scanning, which belongs to the technical field of optical measurement and comprises a broadband light source, two optical fiber isolators, three diaphragms, three auto-collimating lenses, two diffraction gratings, seven plane cylindrical lenses, two linear array photoelectric couplers, a 3-dB coupler, a beam splitter, a longitudinal micro-motion worktable, a transverse micro-motion worktable, a data acquisition card, a signal generator, drive control, a computer and result output. A beat-wave plate is used for scanning a surface to be measured, one linear array photoelectric coupler is used for detecting beat-wave interference signals, the range is half of beat-wave length, the other linear array photoelectric coupler is used for detecting single-wavelength interference signals to determine resolution, and the system is provided with wide range and high resolution. Different ranges can be obtained by adjusting the beat-wave length. Surface three-dimensional measurement can be complete with only one-dimensional scanning, so that mechanism is simplified, and measurement speed is increased. By means of common-path interference, the system is high in interference resistance and suitable for online measurement.